Abstract
A comparison of the loss mechanisms in screen-printed solar cells relative to buried contact cells and cells with photolithography-defined contacts is presented in this paper. Model calculations show that emitter recombination accounts for about 0.5% absolute efficiency loss in conventional screen-printed cells with low-sheet-resistance emitters. Ohmic contact to high-sheet-resistance emitters byscreen-printing has been investigated to regain this efficiency loss. Our work shows that good quality ohmic contacts to high sheet-resistance emitters can be achieved if the glass frit chemistry and Ag particle size are carefully tailored. The melting characteristics of the glass frit determine the firing scheme suitable for low contact resistance and high fill factors. In addition, small toregular Ag particles were found to help achieve a higher open-circuit voltage and maintain a low contact resistance. This work has resulted in cells with high fill factors (0.782) on high sheet-resistance emitters and efficiencies of 17.4% on planar float zone Si substrates, without the need for a selective emitter.
| Original language | American English |
|---|---|
| Number of pages | 11 |
| State | Published - 2004 |
| Event | 14th Workshop on Crystalline Silicon Solar Cells and Modules - Winter Park, Colorado Duration: 8 Aug 2004 → 11 Aug 2004 |
Conference
| Conference | 14th Workshop on Crystalline Silicon Solar Cells and Modules |
|---|---|
| City | Winter Park, Colorado |
| Period | 8/08/04 → 11/08/04 |
NREL Publication Number
- NREL/CP-520-36747
Keywords
- crystal growth
- crystalline silicon (x-Si) (c-Si)
- defects
- device process
- impurities
- materials and processes
- microelectronics
- module
- passivation
- photovoltaics (PV)
- PV
- solar cells